The 'det är' construction

Swedish as a language is very interested in whether things are known to the listener or not. English is too, as compared to languages that don't have the category of definiteness. But sometimes I feel that Swedish takes this obsession just a little bit further than English does. We just take very great care not to shock the people we're talking to by throwing new concepts at them.

In Swedish, when we want to introduce a new concept, we use the construction det är. det in this construction does not refer to the thing introduced. How could it, since that is a new topic that is being introduced to the listener? It would be very illogical to start out by mentioning the gender or number of a thing that has not even been mentioned to the speaker (or so native speakers of Swedish feel).

The det at the start of those sentences does not refer to the house, car or whatever. It is a formal subject that is used to introduce a new concept. It is like the it in 'It is raining'. You could also say that the det here stands for 'what I am going to tell you about next'.

About the use with people – you do something similar in English, as my good friend ViArSkoldpaddor once pointed out: if there's a knock at the door and you know who's there before seeing them, you would say It is my wife, not She is my wife. So with people, the idea is that if you are already talking about a person, and just want to add some more information about her, by all means say Hon är ….
Example: Hon är inte bara tandläkare, hon är min mamma också 'She's not just a dentist, she's also my mom' (to paraphrase a commercial from some years back). But if you're introducing someone for the first time, you say Det här är min syster or in English 'This is my sister'.

About the use with plural: in English, you obviously want the pronoun to agree with the thing introduced. Since you don't have a plural of it, you have to make do with they. In some cases those also works.

So, is it ever possible to say things like den är en bil? It is, if den refers to something that has been mentioned previously in the same sentence. Min bil är inte snabb, men den är en bil. 'My car isn't fast, but it is a car' could be one example.

There is also the case when you point right at one of several items, and stress den when you say den är …. This context would be better translated into English as that one is …. Like, imagine you have several tools spread out on the table, you point at them and say That one is a hammer, that one is a screwdriver …

In the cases where the pronoun refers back to a preceding clause or idea, you must also use det. I'll borrow an example of this from Latif_ in this thread: Vi behöver betala högre skatt, eftersom det är en bra idé 'We need to pay higher taxes, because that is a good idea'. Here, det does not refer to the idea, and not even to the tax, but it refers back to the entire previous clause, so it must be det.

As you may know, this in Swedish is det här or detta, and that is det där (or sometimes just det) . We use those expressions according to the same principles as det in presenting constructions. So you say Det här är en bil for 'This is a car', not den här. And Det där är ett hus would be 'That is a house'.

And also Russian Это and Polish to too, as well as French c'est for everything. I think it might actually be like this in most (indo)European languages. In Latvian though, afaik they use different pronouns, like Tā ir lampa (f) but Tas ir galds (m) (it's a lamp, it's a table) and even when asking about things, so that you have to make a guess at a gender when saying 'What is that?'

Tack så mycket.
Still confuse to me though. I hope I will understand the language better when I study more.
So far, I love studying this language. The more I learn it, the more I understand my Swedish friends.

Oh, I just wrote the ett forms as a representation of the difference between this and that. I was thinking of the Det är … construction, where you wouldn't use the den form. So in the sense that if you say Det här är en bil, 'This is a car', it's true that gender doesn't matter.

If you're thinking about 'this' and 'that' in other constructions, such as 'that book is good', gender matters a lot, so that
'this' = det här or detta or den här or denna
'these' = de här or dessa
'that' = det där or den där or sometimes det or den
'those' = de där

I undeleted yours now, I think it's a good question since what I wrote was unclear!
I should probably write a whole topic about this and that specifically. Can't remember if I've posted anything good about it elsewhere.

Den är så gullig is not an introductory construction. It doesn't even contain a noun, only an adjective. So here you can be totally sure that it must be den or det depending on what the pronoun is referring to.

Den är bilen doesn't really work on its own, it's only possible in a very specific context. You can use den when pointing right at things, but as I said above, that's more like that one is ….

For me I feel like "det är" has two faces:
First, it could be similar to "det finns", as in "det är ett hus", to imply something exist.
Second, it seems to me that it has a descriptive face, as in "det är kallt i vattnet", to introduce an adjective if I may say so.

Anyway, as I learn this language, I feel like it is easy to just grasp the way it works. "It makes sense". As opposite to french that I've been learning since kindergarten; gosh I'll never get it.

Thank you Arnauti for this helpful post. I am a little bit confused though about the last paragraph, the use of det här, detta and det där. Is it like English when we say for example: "we used to talk for hours on the phone. Do you remember that?" Minns du det där? "Someone broke into my computer, gjörde du det där? ". "Season seven of game of thrones will have only seven episodes. Det här är nu."
Are these idiomatic?

My main point in relation to this topic is that if you use det här etc in presenting constructions, they also have the neuter form. So just as you say It is my book 'Det är min bok', not den, you can say Detta är min bok or Det här är min bok for 'This is my book', but you still would not say denna or den här, and you could say Det där är min bok for 'That is my book', but not den där….

As for this and that, as I said, this is det här or detta and that can be det där or det. For your examples, when referring back to a whole clause as in your first example, it's more natural to use det than det där, so it would be most idiomatic to say Minns du det?. In your second sentence, the idiomatic way of phrasing it would be var det du som gjorde det literally 'was it you who did it'. But again, det is more natural when you're referring back to something previously mentioned rather than pointing to something. Whereas it's quite natural to translate 'Are you eating that?' into Äter du det där? [implies pointing to something] (more natural than using just det).

For your last sentence, I don't accept/understand it in English so I can't translate it, but if I can rewrite it to say for instance This episode is airing now, it would certainly be Det här avsnittet sänds nu.

It implies something being stuck, fastened or attached, like a painting on a wall or a sticker glued onto something. It doesn't work on its own for the kind of stuck situation the boats in the harbor are in. The particle verb sitter fast could work for that, but usually we'd just say är fast.

I'm still a little confused... so "det" will always be used if you are introducing something new? for example, you just met someone and said "this is my house" you would use "det"? but if you said "my house is here. this is my house" you would use "den"? sorry i am still in the basics